I went down to the coop today, and found a surprise; feathers lying everywhere in the coop and aviary(outdoor penn). It is time for the chickens to molt. Molting is when the chickens lose all their feathers, and then grow new feathers in their place. In the picture below, Pearl is an example of this happening. You can see her feather shafts growing new feathers, that resemble spikes.
In a few weeks, Pearl will have a new coat of soft feathers.